feat(web): scaffold client-side rendered SPA foundation

- feat: initialize Vite project with React 19, React Router 8, TanStack
  Query, Ant Design 6, and Tailwind CSS 4
- feat: add Oxlint with React/TypeScript rules, strict TypeScript
  config, and layered CSS import order
- docs: add decision record for client-rendered Web foundation with
  React, Ant Design, and Tailwind CSS
- docs: create web roadmap defining architecture boundaries and deferred
  dependencies
- build: pin Node.js 24 in mise.toml

web/README.md

@@ -0,0 +1,18 @@
+# MyGO Web
+
+MyGO's browser client is a pure client-side rendered application built with React, TypeScript, and Vite.
+
+## Development
+
+```bash
+npm install
+npm run dev
+```
+
+## Checks
+
+```bash
+npm run check
+```
+
+The production build is emitted to `dist/` as static assets. See `docs/web-roadmap.md` at the repository root for architecture boundaries and planned dependencies.